1. Field of the Invention
The present invention relates to a device for accelerating an abrasive, which comprises magnetically influenceable particles, especially iron particles, for the treatment of surfaces. The device is provided with magnet coils, which are used as accelerating elements, are arranged along the path of the abrasive, preferably on a pipe, and are energized or de-energized by the magnetic field maximum as a function of the traversing of the abrasive which moves in the coil field.
2. Description of the Prior Art
With one such device, which is disclosed in Swiss Pat. No. 240 861, the abrasive is supplied to the acceleration section at a starting velocity, and is supplied to the subsequent magnet coils as piles from the first two magnet coils, which are energized or de-energized alternately and cyclically with the further magnet coils, which bring about the acceleration of the abrasive. The drawback to this heretofore known method is that the abrasive must have a starting velocity, which must be controlled as a function of the size of the abrasive piles which are fed to the acceleration section; this is the case because too great of a starting velocity leads to clogging of the acceleration section, and hence to failure of the device. In contrast, if the starting velocity is too low, the device operates with a low output, since the optimum quantity of abrasive cannot be accelerated.
An object of the present invention is to provide a device for accelerating an abrasive comprised of magnetically influenceable particles, which device takes the abrasive from a static supply.